Door locking device



1952 L. R. A. G. LEMAIRE 3,066,964

DOOR LOCKING DEVICE Filed Feb. 1, 1960 4 Sheets-Sheet 1 Dec. 4, 1962 L.R. A. e. LEMAIRE 3,066,954

DOOR LOCKING DEVICE Filed Feb. 1, 1960 4 Sheets-Sheet 2 \o 55 I'lIHIIILJ Dec. 4, 1962 L. R. A. G. LEMAIRE DOOR LOCKING DEVICE Filed Feb.1, 1960 4 Sheets-Sheet 3 a w W 4 Y 4 M VY a Q a A x mm 7 r\ W 0 a w 2 n7 W 7 m 4 1 w 4/ J a h w 2 9 Ida/:{ll

m l f/vroF lows PA. 6'. LENA/PE 1952 R. A. s. LEMAIRE DOOR LOCKINGDEVICE 4 Sheets-Sheet 4 Filed Feb. 1, 1960 5 w W a a a J a 5 7 m w 4 5 m2 3 w v WM Mw w w w m VEWTOR lows EA]. G. ZEMA/RE United htares Patent;

:iflhfiflb l Fatentecl Dec. 4, 1962 assess; DQOR LQCKENG DEVTCE LouisRaoul Alphonse Georges Lemaitre, 17 Rue de Charnace, Angers, FranceFiled Feb. 1, 1960, Ser. No. 5,892. Claims priority, application FranceFeb. 4, 1959 (Ziainis. (1. 292173 The consequences of traffice accidentsare frequently worsened by the accidental opening of the doors of theinvolved vehicles, which can occur when due to a twisting of the vehiclebody the edge of the door carrying the latch is drawn apart from theadjacent door lamb of the fixed body portion to such an extent that thelatch member becomes disengaged from the catch member.

The present invention relates to a safety latching device which ensuresthe permanent latching of a vehicle door even under the above mentionedcircumstances and which comprises further improvements.

With these objects in view, at least one of the cooperating lockingmembers of the latching device (that is to say the latch member or thecatch member) is movable in the corresponding portion of the latchingdevice so as to be enabled to move beyond its normal locking position,towards the opposite portion of the latching device, and in thisopposite portion is mounted a magnet which is located in such mannerthat when the latching device is in the door closure position, saidmagnet attracts the movable locking member into engagement with theother locking member.

Due to this feature, even when the egde of the door is accidentallydrawn apart from the adjacent door jamb of the vehicle body, the movablelocking member is drawn along with the opposite portion of the latchingdevice and remains in engagement with the other locking member, so thatthe latching of the door remains effective.

When the movable locking member is the latch memher, opening of thelatching device is effected according to the invention by pushing backthe catch member instead of retracting the latch member. This featureinvolves notable advantages. Thus, the opening of the latching device byretracting the latch member, which must moreover be able to move beyondits normal locking position, would necessitate a complicated and expensive mechanism. Furthermore, the latch member being attracted by amagnet in its locking position, retracting the latch member wouldinvolve detaching it from the magnet and would therefore necessitate agreat force, quite beyond the limits admissible in latching device ofthe considered kind.

According to another feature of the invention, the mutual engagement ofthe latch member and the catch member at the closing of the latchingdevice is effected in part under the action of at least one spring,whereaiter the position of complete locking is accomplished by themagnet attracting the movable locking member. A latching deviceembodying this feature is able to Work very silently, on the one handbecause the depth of the mechanical engagement of the latch member withthe catch member is reduced to only a part of the total depth ofengagement, which is then accomplished by the attraction of the magnet,and on the other hand because the total depth of engagement can itselfbe much smaller than in a conventional latching device.

In fact, in latching devices constructed according to the invention, asthe two cooperating members (the latch member and the catch member) ofthe latching device are held together by the attraction of a magnet, andas one of the said members can move beyond the normal locking positionand thus follow the other member in case the vehicle frame is distorted,it is not necessary, when calculating the depth of total engagementbetween the latch member and the catch member, to take into account themargin for safety which is considered essential in conventional latchingdevices in order that they may not open accidentally as a consequence ofdistortions occurring in the vehicle body during its running, evenwithout an accident.

Whereas in conventional latching devices the depth of mutual engagementof the locking members must be of the order of 10 to 15 mm. and at leastof 8 mm., latching devices according the invention ensure a permanentlocking regardless of distortions occurring in the vehicle body duringthe normal running of the vehicle and even in case of an accident, witha total depth of engagement not exceeding 6 mm., of which. only about 4mm. are effected by mechanical engagement under spring action, while thecomplement is accomplished by magnetic attraction.

Other features of the invention will appear from the followingdescription and the appended drawings relating to two embodiments of theinvention given by way of non limitative examples.

FIGS. 1 to 3 represent horizontal sections of the first embodiment, inwhich the movable locking member is the catch member.

PEG. 1 represents the device in the course of its closing, the latchmember being just about to pass by the end of the catch member.

FIG. 2 represents the device in closed position.

FIG. 3 represents the device still closed, although the edge of the doorhas been accidentally drawn apart from the adjacent door jamb of thefixed body portion.

FIGS. 4 to 11 represent the second embodiment, in which the movablelocking member is the latch member.

FIG. 4 is an elevational view of the closed latching device, taken fromthe outside of the vehicle, the external wall of the door and of part ofthe adjacent door jamb being omitted so as to show the mechanism.

FIG. 5 is a side view showing the mechanism as viewed from the left handside of FIG. 4.

PEG. 6 is a horizontal section on the level XX of FIG. 4.

FIG. 7 is an elevation viewed from the left hand side of FIG. 4, showingonly the catch member of the latch ing device.

FlG. 8 is a horizontal section on the level X-X of FIG. 4, the doorbeing open and all parts being in their positions of rest.

FIG. 9 is a horizontal section on the level X-X of FIG. 4, the doorbeing closed and the latching device being completely engaged under theaction of the magnet.

FIG. 10 is a horizontal section on the level X-X of FIG. 4, showing thecatch member pushed back and the door slightly displaced in the openingdirection.

FIG. 11 is a section similar to that of FIG. 9, showing the latchingdevice still closed although the door jamb of the fixed body portionadjacent to the door has been accidentally drawn apart from the latter.

Referring to the first embodiment, FIGS. 1 to 3 show at 13 the casing ofthe latching device mounted at the edge of the door indicated at 1 indotted lines. In the casing 18 slides the latch member 19 which issubmitted to the action of a spring lit. The retraction of the latchmember 19 in order to open the door is effected by drawing the handle 21in the direction of the arrow, so that the arm 22 of the handle pushesback the collar 23 of the latch member 19.

The reference 24 designates a sheath which is mounted in the iambportion of the fixed part of the vehicle body indicated in dotted linesat 2. In the sheath 24 slides the catch member 25 which cooperates withthe latch osages member 19. To the end of the catch member 25 is securedan armature 25a made of metal which is attracted by a magnet, forexample of iron or steel. The catch member 25 is drawn to the inside ofthe sheath by a spring 2-6 whose rear end is secured to a screw-threadedplug 27 screwed into the rear end of the sheath 24, whereby the tensionof the spring 26 may be adjusted. After adjustment, the plug 27 islocked by a lock-nut 28. The end of a screw 8 which engages alongitudinal groove in of the catch member 25 prevents the latter fromturning (if it is cylindrical) and limits its sliding movement out ofthe sheath 24.

In front of the outer surface of the latch member 19, a permanent magnet29 is mounted on the casing 18 by means of a bracket 36 secured by ascrew 31.

As shown on FIG. 1, the relative positions of the latch member 19 and ofthe armature 25a of the sliding catch member 25' are such that the endof the latch member 19 brushes past the armature 25a when the door 1closes. But the catch member 25 with its armature 25a may also be placedso as to project slightly more towards the door 1, so that on closingthe latter the latch member 19 will be slightly pushed back when itmoves past the armature 25a and said latch member will engage slightlybehind said armature when it resumes its former position due to thethrust of the spring 20.

As soon as the outer surface of the latch member 19 has passed the inneredge of the armature 25a, the latter is attracted by the magnet 29, thecatch member 25 slides out of the sheath 24 until it reaches theposition shown on FIG. 2 and the door is latched due to the mutualengagement of the latch member 19 and the armature 25a of the catchmember 25.

When the door It and the adjacent jamb portion 2 of the vehicle body areaccidentally drawn apart, the magnet 29 draws along the armature 25a andthe catch member 25, the latter sliding more or less out of the sheath24, so that the door remains securely latched, as represented on FIG. 3.

Referring now to the second embodiment represented on FIGS. 4 to 11, thereference 41 designates a supporting plate which carries the mechanismof the latching device and is mounted adjacent the edge of the vehicledoor 42.

The reference 4 3 designates the catch member casing which is mounted inthe door jamb of the fixed body portion 44 of the vehicle by means of aguard-plate 45 and a nut 46 screwed on a screw bolt 47 integral with thecasing 43.

The latching device mechanism comprises a latch member 48 which isslidably mounted in a bracket 4& and through an aperture formed in theraised edge 41a of the plate 41. A leaf spring 56 secured at 51 to theplate 41 pushes the latch member 48 towards the right hand side of FIG.4, but has its stroke in this direction limited by a stop 52 fixed onthe plate ll. Another stop 53 limits the stroke of the spring 56 in theopposite direction. A coil spring 54 attached at 55 to the bracket 49and at 56 to the latch member 4% draws the latter towards the left handside of FIG. 4, but this Spring 54 is less strong than the spring StConsequently, at rest the spring 56 leans against the stop 52 and therear end of the latch member 43 leans against the spring 56' (see FIG.8).

In the catch member casing 43, a movable catch member 57 is pivotallymounted on a vertical pin 58. This movable catch member is formed withthe conventional safety notch 59 followed by the closing notch proper65b for engagement with the latch member 48. A spring 61 tends to holdthe movable catch member 57 in the position of rest shown on FIGS. 6, 8,9 and 11, but the catch member 57 can be pushed back into the casing 43under compression of the spring 6-1, as shown on FIG. 10.

Behind the closing notch 6i), a permanent magnet 62 is mounted in thecasing 43, said magnet facing exactly 4 the front end of the latchmember 48 when the latching device is closed. The mechanism for openingthe latching device, which operates by pushing back the movable catchmember, com

prises a push-rod 63 which is slidable in parallel rela-' tion to thelatch member 4% in the bracket 49 and through an aperture formed in theraised edge 41a of the plate 41. When the latching device is closed, theend of the pushrod 63 faces exactly the portion of the movable catchmember 57 which is designated on FIG. 7 by the small rectangle in dottedlines 63a. The push-rod 63 is actuated by a three-armed lever 64, 65, 66which is pivotally mounted at 67 and whose arm 64 engages by its forkedend a small pin 6%; fixed on the push-rod 63. A spiral spring 69 tendsto turn the lever 64, 65, 66 anticlockwise as viewed on FIG. 4.

The clockwise rocking of the lever 64, 65, 66, which causes the openingof the latching device as it will be explained below, may be caused bymeans of a bell crank lever pivotally mounted at 71 on the raised edge41a of the plate 43 and the bent end portion 72 of which car? be pushedback by a push-button (not shown) from the outside of the vehicle door.The lever 76 is shown as a whole on FEGS. 5, 6 and 8 to 11, whereas onlyits inner arm is represented in cross section on FIG. 4.

Alternatively, the same clockwise rocking of the lever 64, 65, 66 may becaused also by means of a link 73 which is controlled by a handle (notshown) from the inside of the door, said link being connected to thelever arm 66 by means of a slot 74 engaging a pin 75 fixed on said arm.

The operation of the second embodiment of the latching device will nowbe described with reference to FIGS. 8 to 11.

On FIGS. 8 to 10, the are A drawn in dotted lines represents the pathfollowed by the outer end of the latch member 48 when it is in itsposition of rest, that is to say when its rear end leans under theaction of the spring 54 against the spring 50 which leans itself againstthe stop 52, as shown on FIG. 8. It can be seen that this path passes ata point located between the closing notch 60 of the movable catch member57 and the pole surface of the magnet 62, so that upon closing the door'the mutual engagement of the latch member 48 and catch member 57 will beaccomplished in part by the action of the spring 50 and in part by theattraction of the latch member 48 by the magnet 62, as it will now bedescribed.

Starting from the position shown on FIG. 8, when the door is pushedtowards the closed position shown on FIG. 9, the front end of the latchmember 48passes first over the notch 59 and then over the notch 60, thispassage being permitted in part by the recoil of the latch member 43 tothe left under compression of the spring 50 and in part by the recoil ofthe movable catch member 57 towards the right against the action of thespring 61 (assuming that the springs 50 and 61 are of substantiallyequal strength).

As soon as the latch member 48 has snapped in behind the notch 6tl, itsfront end is sufliciently near the magnet 62 to be attracted by thelatter, overcoming the pull of the spring 54, and the latch member 48 isdrawn against the pole surface of the magnet 62 as shown on FIG. 9, therear end of the latch member 48 being drawn apart from the spring 50 (asshown on FIGS. 9 and 4).

When it is desired to open the door, one may act upon the outerpush-button (not shown) which pushes back the end portion 72 of thelever 70 and turns the latter anticlockwise as viewed on FIG. 5, or onemay act upon the inner door handle (not shown) which draws the link 73to the left as viewed on FIG. 4. In either case the lever 64, 65, 66 isrocked clockwise as viewed on FIG. 4, so that the push-rod 63 is movedto the right and pushes the movable catch member 57 back until its notch60 comes to lie behind the pole surface of the magnet 62 (see FIG. andthe door can be opened. As soon as the front end of the latch member 48has slid away from the pole surface of the magnet 62, the latch member48 is no more attracted and recedes instantly under the action of thespring 54 to its position of rest, as shown on FIG. 10, so that the doormay be swung open freely.

The total depth of engagement of the end of the latch member 48 behindthe notch 60 of the catch member 57 does not need to be calculated withthe usual margin for safety, because this depth of engagement is ensuredindependently of the distortions which may occur in the vehicle bodyduring the running of the latter. This security is due to the fact thatthe latch member 48, which is able to slide outwards beyond its positionof total engagement shown on FIG. 9, remains in all circumstancesadherent to the magnet 62, even when the jamb portion 44 of the vehiclebody comes slightly apart from the door 42.

Since the latch member 48 is able to slide outwards well beyond itsnormal closing position, the latching of the door remains ensured evenwhen the jamb portion 44 of the vehicle body is moved farther apart fromthe door 42, for instance in an accident, as shown on FIG. 11, where thelatch member 48 has nevertheless remained in contact with the magnet 62and engaged behind the notch 69 of the catch member 57, due to the factthat the latch member 48 has slid to the right, tensioning the spring54.

The relatively small depth of engagement which is required in thelatching device according to the invention makes the operation of thelatter particularly silent, thus providing a solution for a problem ofpresent interest, the noiseless closing of vehicle doors.

It will be understood that the invention is not limited to theembodiments which have been described and shown by way of example, butincludes also any other embodiments presenting the same features, withinthe scope of the following claims.

I claim:

1. A door latching device comprising a latch member casing, a latchmember movably mounted in said latch member casing, a catch membercasing, a catch member yieldably mounted in said catch member casing soas to be movable between an outer and an inner position, resilient meansurging said catch member towards its outer position, said latch memberbeing spring held in a normal position for partial engagement with saidcatch member when said catch member is in its outer position, magneticmeans on said catch member casing for attracting said latch memberbeyond normal position into full catch member engaging position, saidlatch member being movable beyond said full catch member engagingposition, and means for moving said catch member to its inner position,out of engagement with said latch member.

2. A door latching device as claimed in claim 1, comprising a firstspring urging said latch member toward catch member engaging position, astop member limiting the extension of said first spring at a pointcorresponding to said normal position of said latch member, and a secondspring urging said latch member from catch member engaging position intoengagement with said first spring, said second spring being less strongthan said first spring.

3. A door latching device as claimed in claim 1, wherein said means formoving said catch member comprise a push-rod movably mounted in saidlatch member casing and means for moving said push-rod into engagementwith said yieldably mounted catch member.

4. A door latching device as claimed in claim 1, wherein said means formoving said catch member comprise a push-rod movably mounted in saidlatch member casing, actuating elements on both faces of said latchmember casing and transmission means connecting said actuating elementsto said push-rod for moving said pushrod into engagement with said catchmember upon actuation of either of said actuating elements.

5. In a door latching construction a fixed support element, a swingablesupport element, a latch member carried by one of said elements, a catchmember carried by the other of said elements, one of said members beingresiliently urged toward engagement with the other member and having acam surface adapted to be engaged by said other member to wedge said onemember out of the path of said other member during closing movement ofthe door, said latch and catch members interengaging in latched positionto lock the support elements in closed position when said elements arealigned, said other member being slidably retained in its element andurged away from said one member, and a magnet fixed to the same elementas carries said one member and ar' ranged to attract said other membertoward said one member after interlocking engagement has been efliectedto a position effecting a greater degree of interlocking whereby even ifsaid support elements are accidentally pulled apart while still alignedthe members will remain latched together.

6. In a door latching construction, the combination as described inclaim 5 wherein is additionally provided mechanical means for movingsaid one member against the resilient urging thereof whereby to unlatchsaid members and permit relative swinging between said support elements.

7. In a door latching device, a stationary support, a support movablelaterally into and out of alignment with said stationary support,interengaging means on said supports for releasably retaining saidmovable support in a position in alignment with said stationary support,said means including a latch member on one of said supports, a catchmember on the other of said supports and engageable with said latchmember when the movable support is moved to said position, means urgingthe member on said movable support toward engagement with the member onthe stationary support, said movable support member having a cam surfacearranged to engage the stationary support member so that when themovable snpport is moved toward said position said movable supportmember momentarily is moved against the force of the urging means topermit said members to engage, means mounting the stationary supportmember for sliding movement through a limited path, at least a portionof the stationary support member facing the other member being formed ofa magnetically attractive material, and magnetic means on said movablesupport for attracting said stationary support member portion andretaining the stationary support member in engagement with the movablesupport member, whereby said interengaging means are operative even whenthe movable support is displaced longitudinally of the movable sup portmember.

8. In a door latching device, a stationary support, a support movablelaterally into and out of alignment with said stationary support,interengaging means on said supports for releasably retaining saidmovable support in a position in alignment with said stationary support,said means including a latch member on said movable support, a catchmember on said stationary support and engageable with said latch memberwhen the movable support is moved to said position, said catch memberhaving limited movement in the frame, means urging the latch membertoward engagement with the catch member, said latch member having a camsurface facing the direction of movement of said movable support so thatwhen the movable support is moved toward said position said latch membermomentarily is moved against the force of the urging means to permitsaid members to engage, means mounting the catch member for slidingmovement through a limited path, at least a portion of the catch memberfacing the latch member being formed of a magnetically attractivematerial, and magnetic means on said movable support for attracting saidcatch member portion and retaining the catch member in engagement withthe latch member, whereby said interengaging means are operative evenwhen the movable support is displaced longitudinally of the movablesupport member.

9. A door latching device comprising a latch member casing, a latchmember mova-bly mounted in said latch member casing, said latch memberbeing urged outwardly of said casing and having a cam surface adapted tomove the latch member inwardly of said casing when engaged by a catchmember, a catch member casing, said casings being laterally movable withrespect to each other from open to aligned closed position, a catchmember movably mounted in said catch member casing and spring held to arestricted normal position engaging said latch member in said closedposition of the casings, said catch mem ber being movable outwardly ofits casing beyond its retracted normal latch member engaging position,magnetic means on said latch member casing for attracting said catchmember outwardly of its casing from its normal position to a projectingposition for fuller engagement with said latch member, and means forwithdrawing said latch member from engagement with said catch member.

10. A door locking device comprising a latch member and a catch membermovable relative to each other and having a normal interengaging lockingposition securing said device in closed position, resilient meansoperative upon at least one of said members and urging said member tonormal locking position for causing positive locking interengagement ofsaid members automatically upon movement thereof to closed position, atleast one of said members being movable beyond its normal positivelocking position, magnetic means for attracting said movable member whenengaged with the other of said members and drawing said movable memberinto further engagement for preventing independent disengaging movementof said movable member from positive locking engagement with the otherof said members, and manually operable means cooperative with one ofsaid members for moving said member out of normal locking position.

References Cited in the file of this patent UNITED STATES PATENTS1,102,118 Yurow June 30, 1914 2,219,186 HOIIlfCCk Oct. 22, 19402,586,900 Alderman Feb. 26, 1952

